CPT® Code 64642

Chemodenervation is a medical procedure aimed at alleviating involuntary muscle contractions or spasms that can occur in various conditions such as dystonia, cerebral palsy, or multiple sclerosis. This procedure specifically targets the muscles of one extremity, which may be affected by these involuntary movements. The technique involves the injection of botulinum toxin, either type A or B, directly into the muscle. This toxin works by inducing temporary muscle paralysis through the inhibition of acetylcholine release at the peripheral nerve endings. By blocking this neurotransmitter, the procedure effectively interrupts the neuromuscular transmission of nerve impulses, leading to a reduction in muscle activity and spasticity. Prior to the injection, the healthcare provider determines the specific muscle or muscle group to be treated. This assessment can be conducted using electromyography, a diagnostic procedure that evaluates the electrical activity of muscles, or through a physical examination of the affected extremity. During this examination, the provider palpates the muscles and identifies the precise locations of muscle spasms. Once the appropriate sites are identified, the extremity is prepared for the procedure, ensuring a sterile environment. The injection is then administered at carefully selected sites within the affected muscle or muscle group to achieve the desired denervation effect. For coding purposes, the CPT® code 64642 is used for the chemodenervation of 1-4 muscles in one extremity, while 64643 is designated for 1-4 muscles in each additional extremity.